Help please 😞 pet rooster cant stand without falling

Hi guys! I've been lurking around here for awhile now. But I've got a problem I can't seem to find a answer for. So I'm hoping someone can point me in the right direction.

My RIR roo is about 3 yrs old. While he was young we had a freak snow storm for Alabama and somehow his feet got frost bite. Of course I started researching to see if he could survive this and he did. He just got to be baby for a few months until his toes finally fell off. But now he runs around on his little nubs like nothing ever happened. And yes, he's a bit spoiled but he deserves it.

The last week he hasn't been acting like himself. He would have his head tilted to the side, he would sneeze ever so often and mucus would fly from his nose.
Earlier this morning he fell over and began to flop on the floor. A few hrs later he seemed perfectly fine, walking around, eating, etc. Tonight he was unable to stay upright at all. I've brought him in the house hoping he may just have a cold and the congestion may be causing most of the problem. But if he tries to move at all he starts falling over and flopping again. He has been laying still for hrs now under a warm blanket with his head laying over on a pillow. He can no longer hold his head upright at all, it stays tilted to the side. Ever so often he tries to get up and we start the process of calming him over again.

I don't kno if I'm just being hopeful or not but I think I've been seeing a pattern of this happening and just didn't think anything of it because he does loose his balance at times normally. But since it's been getting chilly over the last few days it seems to have gotten worse.

I've been racking my brain trying to figure out what may be wrong but I've gotten my thoughts stuck in the weather change/a possible cold being the problem. So does anyone have any idea of what may be going on that I'm over looking? Or just something I haven't thought of?

Other information that may or may not be needed:
He seemed to have been eating fine the last few days. Had no problem running the dogs away from the dog food earlier today actually.
I honestly don't kno about his poop.
No injuries that I can see.
He was dusted for mites about 3 weeks ago. (Just a routine dusting)

Welcome to BYC. I really do not know what his problem is, but he sounds very sick. I would take him to a vet, or call your state vet and ask about any unusual diseases that are being seen. It sound like he may have wry neck or torticolis, which sometimes accompany a severe respiratory disease or Mareks. Was he vaccinated for Mareks disease? Put some vitamins and electrolytes in his water, and try to get him to drink. I would get him tested, and if he should not make it, refrigerate his body and send it to the state vet for a necropsy. Here is a link for that: http://www.usaha.org/Portals/6/StateAnimalHealthOfficials.pdf